6061 aluminum sheet, a typical representative of aluminum-magnesium-silicon alloys, has become a mainstream material in the field of electronic heat dissipation due to its balanced thermal conductivity, mechanical properties, and processability. Different tempers exhibit significant differences in thermal conductivity, strength, and processability, with T4, T6, and T651 tempers being the most suitable for electronic heat dissipation applications.
6061-t4 aluminum
It has a thermal conductivity of approximately 154 W/(m·K), a tensile strength of 230 MPa, a yield strength of 130 MPa, and an elongation of 10%-18%. This temper exhibits excellent cold formability, easily enabling complex processing such as bending and stamping, making it suitable for manufacturing irregularly shaped heat dissipation components. However, its strength is relatively low, limiting its suitability only to the heat dissipation needs of low-power electronic devices.
6061-t6 Aluminum
6061 t6 aluminum sheets undergo artificial aging treatment at 350-500°F (approximately 177-260°C) for 12-24 hours, precipitating a Mg₂Si strengthening phase. This increases their thermal conductivity to 167 W/(m·K), tensile strength to 310 MPa, yield strength to 270 MPa, and hardness to 93 Brinell.
6061 t6 aluminum achieves a perfect balance between thermal conductivity and strength, making it the most widely used state in electronic heat dissipation, suitable for both heat dissipation and structural support requirements of medium-to-high power devices.
6061-t651 aluminum
After T6 heat treatment, it undergoes 1.5%-3% cold stretching to offset residual stress, reducing residual stress by over 70%, with processing deformation only 1/5 that of T6. Its thermal conductivity is close to T6 (approximately 165 W/(m·K)), and its strength is essentially the same. Its core advantage is excellent dimensional stability, making it suitable for manufacturing high-precision heat dissipation components.
Typical applications
1. High-power computing equipment
High-performance computing chips such as CPUs and GPUs (e.g., server clusters, core components of gaming PCs) generate extremely high amounts of heat during operation, requiring heat dissipation components to combine efficient thermal conductivity with structural stability. Common applications include liquid cooling plates and heat sink fin assemblies. Liquid cooling plates require brazing (brazing furnace temperatures can reach 600℃), demanding high high-temperature stability of the material.
The T6 temper, with its high thermal conductivity of 167W/(m·K) and balanced strength, is the preferred choice for these components. For components with extremely high dimensional accuracy requirements, such as server CPU cooling plates, the T651 temper is preferred. Its extremely low residual stress prevents deformation after processing, ensures the sealing of coolant channels, and guarantees stable heat dissipation efficiency.
2. New energy vehicle electronics
Core electronic components of new energy vehicles, such as power battery packs, motor controllers, and on-board chargers, are key targets for heat dissipation system control. 6061 aluminum plates are primarily used for battery cooling and controller heat sink housings. When the power battery cells are operating, a cooling aluminum plate is used to create a heat dissipation channel, allowing coolant to flow through and carry away heat, preventing overheating and potential safety hazards.
This type of cooling aluminum plate must withstand both coolant pressure and vehicle vibration. The high strength and good weldability of the T6 temper meet the structural requirements, and it can be precision rolled to achieve an ultra-thin profile of 0.03mm, adapting to the miniaturization design needs of battery packs.
The heat dissipation housing of the motor controller is formed by stamping T6 aluminum plate, balancing heat dissipation efficiency and impact resistance, ensuring stable operation of the controller under complex conditions.
3. Consumer Electronics
Consumer electronics such as mobile phones, tablets, and laptops have higher requirements for the lightweight and formability of heat dissipation components. Applications include laptop cooling fan housings and auxiliary heat sinks for mobile phone mid-frames.
Among these, auxiliary heat sinks for mobile phone mid-frames need to conform to complex curved surfaces and have extremely strict weight control. The high elongation of the T4 temper allows for complex bending and stamping, while offering significant lightweight advantages. Although the strength is moderate, it is sufficient to meet the low-stress requirements of consumer electronics.
Laptop cooling fins and fan housings utilize the T6 temper, ensuring lightweight design while providing sufficient structural strength to prevent component deformation due to vibration after long-term use, thus extending the lifespan of the cooling system.
4. Communication and aerospace electronics
Microwave communication equipment and aerospace electronic components (such as heat dissipation modules for aircraft fuel lines) have extremely stringent requirements for the precision and stability of heat dissipation components. Applications primarily utilize high-precision heat dissipation substrates and customized heat dissipation cavities.
The heat dissipation components of such equipment are mostly complex and irregularly shaped structures, and need to work for a long time in extreme environments (high temperature, vibration). The dimensional stability and high reliability of the T651 state become the core selection criteria - its processing deformation is only 1/5 of that of the T6 state, which can accurately match the precision assembly requirements.
At the same time, alu 6061’s good corrosion resistance and welding performance can adapt to the harsh working conditions of aerospace and communication equipment, ensuring the heat dissipation stability and service life of electronic components.